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YGRose

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Hi All, first time poster here in a muddle.

I've got a mobile unit that's currently being wired up and I'm struggling to work out which consumer unit to use. Ideally the smaller the better as it's technically mobile, I would like to be able to use an industrial 3 pin plugin on it. I believe these go up to 63a as a blue euro pin.

I've currently got:
Lighting ring - Led but on 230V
Smoke Alarm - Lighting ring
Fans - On the lighting ring also
Mains Socket ring
Underfloor Heating @ below 1500w (prehaps 1250w)
Kitchen ring - Oven Fuse Spur
Electric Water Heater @ 11KW - Specifies 48A

Can anyone help with what Consumer Unit I can get away with? I'd really like to avoid trailing a 100a SWA and need for such a large load.

My guessing is for MCB's (MK) I'll need 1x6A 1x 16A 2x32A 1x50A to cover this. My question is, what RCD and Consumer Unit do I need for this?

Massive thanks in advance as this has been bothering me for a while!!
 
What sort of mobile unit and what is its intended purpose/use?
 
Where is the unit going to be plugged in, do they have a suitable supply and outlet?
Or are you using a generator?

Whoever is doing the Electrical installation in this unit should be working out cable sizes / circuits C.U type and size.
 
Hi All, first time poster here in a muddle.

I've got a mobile unit that's currently being wired up and I'm struggling to work out which consumer unit to use. Ideally the smaller the better as it's technically mobile, I would like to be able to use an industrial 3 pin plugin on it. I believe these go up to 63a as a blue euro pin.

I've currently got:
Lighting ring - Led but on 230V
Smoke Alarm - Lighting ring
Fans - On the lighting ring also
Mains Socket ring
Underfloor Heating @ below 1500w (prehaps 1250w)
Kitchen ring - Oven Fuse Spur
Electric Water Heater @ 11KW - Specifies 48A

Can anyone help with what Consumer Unit I can get away with? I'd really like to avoid trailing a 100a SWA and need for such a large load.

My guessing is for MCB's (MK) I'll need 1x6A 1x 16A 2x32A 1x50A to cover this. My question is, what RCD and Consumer Unit do I need for this?

Massive thanks in advance as this has been bothering me for a while!!
Have you considered having a gas water heater? what KW is the Oven? will you be installing some sort of intruder alarm for out of business hours? what type, size of Fans will you require? I'm not sure what the regulations are for air changes in a mobile catering unit?
'






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Sorry, I'll try to be more specific. I'm just trying to keep the connection from the house to the unit as small as possible (and user friendly)

The unit is for an office/guest room in the garden. It will likely be fed from a nearby house. There is no alarm system planned currently. While the unit is mobile and road legal, once placed it will probably stay long term.

Lighting is a loop-in radial system with 12x 4.8W LED downlights and a 6W 100mm bathroom fan with timer. There are trickle vents on the windows regarding airflow and a possible extra fan for the kitchen.

The Heater is electric @ 11KW with 10mm cable. I know gas would use drastically less but I wanted an on demand tankless system and to only use water/electric for simplicity sake.

The mains socket ring has 6x double sockets, two of which will have USB

Underfloor heating specifies 16A is the maximum for the thermostat and at 1250W should be fine

Kitchen will have a small oven, rated @ 13A which I presume can be a fused spur but if there is an induction hob I imagine a 32A fused spur to the box with 6mm cable will be needed

Let me know if there is anything else!!
 
Sorry, I'll try to be more specific. I'm just trying to keep the connection from the house to the unit as small as possible (and user friendly)

The unit is for an office/guest room in the garden. It will likely be fed from a nearby house. There is no alarm system planned currently. While the unit is mobile and road legal, once placed it will probably stay long term.

Lighting is a loop-in radial system with 12x 4.8W LED downlights and a 6W 100mm bathroom fan with timer. There are trickle vents on the windows regarding airflow and a possible extra fan for the kitchen.

The Heater is electric @ 11KW with 10mm cable. I know gas would use drastically less but I wanted an on demand tankless system and to only use water/electric for simplicity sake.

The mains socket ring has 6x double sockets, two of which will have USB

Underfloor heating specifies 16A is the maximum for the thermostat and at 1250W should be fine

Kitchen will have a small oven, rated @ 13A which I presume can be a fused spur but if there is an induction hob I imagine a 32A fused spur to the box with 6mm cable will be needed

Let me know if there is anything else!!
Don't know what you mean by a 32 A fused spur for the Induction hob.? can you please elaborate?
 
The property you are going to supply this from is it single phase or three phase?

Earthing arrangement, TT or TN?

What size is the supply fuse etc?
 
I just mean a hardwired dedicated cooker circuit. It's not actually having the kitchen built until after (haven't specified size of kitchen) so I just want to "future proof it" with a big red switch.

I believe the property is single phase. Not sure about earthing arrangement and probably 100A service head coming in. I think it's the most common arrangement...
I was hoping I could take something like a 2P+E trailing plug for this.

My concern is for the inside of the unit and having enough power while making it easy on the sparky on the other end to connect it up.
 
Without knowing the available supply characteristics then it is difficult to design an installation.

I would recommend you contact a local electrician to pay a site visit with you to ascertain the the incoming supply details and go from there.

If gas is available it would be much easier to utilise that for heating and hot water rather than electricity, this would be cheaper on installation and running costs.
 
I can't do that as no single site does exists, just a few maybes. I am trying to work out what I need on the consumer unit side of things within the unit. As it currently does not have a home I can't give any specifics as to what the incoming options are, that would be up to another electrician on their side. Simply put I'm looking for the easiest way to hook the unit up and cater to its power needs.

I have stated I'm aware of the tankless gas heaters pulling less, although electric is actually cheaper to install, longer lasting and much more efficient.
 
////
Never seen a 32A FCU, but a 16A one exists according to B&Q

View attachment 55683
Precisely the reason they shouldn't be selling these things to Mr and Mrs Public. it's limited to 13Amps. only the uninformed public could be conned into buying this for the purpose the Opening post requires.
 
Yes, I meant a cooker switch. Sorry, it's been a really busy day and my mind is all over the place. If I were to have a double induction hob on a 13A plug and a small oven on a 13A plug also then I seem to be looking at:

1x6A
1x16A
2x32A
1x50A

Would this have to be on a 100A consumer unit? I see it adds up to 136A without diversity.
 
I'm confused, are you manufacturing this unit for sale to the general public?
 
I can't do that as no single site does exists, just a few maybes. I am trying to work out what I need on the consumer unit side of things within the unit. As it currently does not have a home I can't give any specifics as to what the incoming options are, that would be up to another electrician on their side. Simply put I'm looking for the easiest way to hook the unit up and cater to its power needs.

I have stated I'm aware of the tankless gas heaters pulling less, although electric is actually cheaper to install, longer lasting and much more efficient.

Without knowing where it will be you can't know what size of supply is available, or the earthing and binding arrangements required.

This will likely need a 63A supply with that big water heater in it, but until you know where it is going you won't know how much capacity is available for it.

What is the unit constructed from, is there any metalwork? Is it a metal structure. Being road legal it presumably is built on some kind of trailer base, with wheels and stabilising legs? In which case for some types of electricity supply it will need to have its own earthing system created by the installation of earth rods as it could be dangerous to use the installations earth, for other types of supply it will be fine to use the installations earth.
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Ideally the smaller the better as it's technically mobile, I would like to be able to use an industrial 3 pin plugin on it. I believe these go up to 63a as a blue euro pin.

Can anyone help with what Consumer Unit I can get away with? I'd really like to avoid trailing a 100a SWA and need for such a large load.

Ceeform connectors are available in 16A,32A,63A and 125A

You will 'get away with' a consumer unit which has enough ways to serve all of the circuits you have. As far as I can see you have 5 or possibly 6 circuits so a 6 way CU will probably suffice (I can't see much need for spare ways in this application)
As for the physical size you'll just have to read datasheets to see how big they are, although choosing the smallest one will make it more awkward to work on.
You need to decide which circuits require RCD protection based on what they are doing and how they are installed.

If you are connecting it via a Ceeform plug it will use a trailing lead made from flexible cable to connect it, not an SWA. SWA is not suitable for making trailing leads.
 
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